Compilare: user.c: In function ‘main’: user.c:20:4: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(!n&&c-f[0]==4) ^ user.c:27:5: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(o%2) ^ user.c:9:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("pal.in","r",stdin),freopen("pal.out","w",stdout),scanf("%d",&l); ^ user.c:9:37: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("pal.in","r",stdin),freopen("pal.out","w",stdout),scanf("%d",&l); ^ user.c:9:65: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("pal.in","r",stdin),freopen("pal.out","w",stdout),scanf("%d",&l); ^ user.c:11:8: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&f[i]),c+=f[i]; ^